Increasing the efficacy of recycling agents with simultaneous addition of zinc diethyldithiocarbamate as an antioxidant

2021 ◽  
Vol 271 ◽  
pp. 121892
Author(s):  
Hamzeh F. Haghshenas ◽  
Elham Fini ◽  
Robert Rea ◽  
Ali Khodaii
Keyword(s):  
Simultaneous Addition ◽  
Zinc Diethyldithiocarbamate

Fibrinogen and its Derivatives: Cofactors in the Intrinsic Generation of Thrombin

1976 ◽  
Vol 35 (02) ◽  
pp. 305-313 ◽  
Author(s):  
D.C Triantaphyllopoulos ◽  
L.T Ryan
Keyword(s):  
Factor Viii ◽  
Vitamin K ◽  
Bovine Serum ◽  
Thrombin Generation ◽  
Factor V ◽  
Simultaneous Addition ◽  
Lower Effect

SummaryThe simultaneous addition of suboptimal concentrations of factor VIII and intact or plas-min-lysed fibrinogen into mixtures of the vitamin K dependent factors, phospholipids, adsorbed bovine serum (supplier of factor V) and calcium, increased the amount of thrombin which was generated three to twenty times over the sum of the amounts which were generated when factor VIII, or fibrinogen, or its derivatives were added separately into the thrombin generating mixture. When factor VIII was added together with both fibrinogen and its derivatives, the amount of thrombin generated was even greater, about 130% larger than the amount which was generated in the presence of equal concentrations of only intact fibrinogen plus factor VIII. Addition of albumin instead of fibrinogen or its derivatives has a similar but significantly lower effect on thrombin generation. It appears, therefore, that both intact fibrinogen and its plasminolytic derivatives, singly or in combination, and to a lesser extent albumin, act as cofactors in the reaction which is regulated by factor VIII.

Interaction between parathyroid hormone and prostaglandin E1 on cyclic AMP metabolism in rat kidney

1980 ◽  
Vol 93 (3) ◽  
pp. 339-345 ◽  
Author(s):  
Naokazu Nagata ◽  
Yuriko Ono ◽  
Narimichi Kimura
Keyword(s):  
Parathyroid Hormone ◽  
Cyclic Amp ◽  
Adenylate Cyclase ◽  
Rat Kidney ◽  
Prostaglandin E ◽  
Cortical Tissue ◽  
Newborn Rat ◽  
Simultaneous Addition ◽  
Renal Cortical Tissue ◽  
Subsequent Addition

Abstract. The interaction between parathyroid hormone (PTH) and prostaglandin E1 (PGE1) in influencing cyclic AMP metabolism in rat renal cortical tissue was examined. PTH and PGE1 stimulated additively the adenylate cyclase activity in the homogenate of the tissue. Both PTH and PGE1 enhanced the level of cyclic AMP in the incubated renal cortical tissue, but the effect of their simultaneous addition did not exceed the effect induced by PTH alone. Cyclic AMP accumulated in the incubation medium by stimulation by PTH was decreased by the simultaneous addition of PGE1. When the tissue was pre-incubated for 30 min with 2 to 10 μg/ml of PGE1, the magnitude of the increase of cyclic AMP caused by PTH subsequently added was lessened. However, the response to PTH of adenylate cyclase preparation obtained from the homogenate of PGE1-pre-treated tissue was not decreased. When first PTH was added to the incubating renal cortical tissue, the subsequent addition of PGE1 accelerated the decrease of cyclic AMP content in the tissue and decreased the amount of cyclic AMP released from the tissue. The interaction of PTH and PGE1 on cyclic AMP metabolism in the renal cortical tissue was in contrast to that seen in newborn rat calvaria where PGE1 and PTH acted additively in enhancing the level of cyclic AMP.

Influence of simultaneous addition of MnO2 and CoO on properties of SnO2-based ceramics

2000 ◽  
Vol 46 (1) ◽  
pp. 39-43 ◽  
Author(s):  
A Dibb ◽  
S.M Tebcherani ◽  
W Lacerda ◽  
M.R.C Santos ◽  
M Cilense ◽  
...  
Keyword(s):  
Simultaneous Addition

scholarly journals Properties of cytosolic components activating rat hepatic 5-deiodination in the presence of NADPH

1986 ◽  
Vol 234 (2) ◽  
pp. 391-398 ◽  
Author(s):  
K Sawada ◽  
B C W Hummel ◽  
P G Walfish
Keyword(s):  
Enzyme Activity ◽  
Glutathione Reductase ◽  
Rat Liver ◽  
Column Chromatography ◽  
Reduced Glutathione ◽  
Hydrogen Acceptor ◽  
Simultaneous Addition ◽  
Heat Stable ◽  
Hepatic Microsomes ◽  
Normal Rat

The effects of cytosol, NADPH and reduced glutathione (GSH) on the activity of 5′-deiodinase were studied by using washed hepatic microsomes from normal fed rats. Cytosol alone had little stimulatory effect on the activation of microsomal 5′-deiodinase. NADPH had no stimulatory effect on the microsomal 5′-deiodinase unless cytosol was added. 5′-deiodinase activity was greatly enhanced by the simultaneous addition of NADPH and cytosol (P less than 0.001); this was significantly higher than that with either NADPH or cytosol alone (P less than 0.001). GSH was active in stimulating the enzyme activity in the absence of cytosol, but the activity of 5′-deiodinase with 62 microM-NADPH in the presence of cytosol was significantly higher than that with 250 microM-GSH in the presence of the same concentration of cytosol (P less than 0.001). The properties of the cytosolic components essential for the NADPH-dependent activation of microsomal 5′-deiodinase independent of a glutathione/glutathione reductase system were further assessed using Sephadex G-50 column chromatography to yield three cytosolic fractions (A, B and C), wherein A represents pooled fractions near the void volume, B pooled fractions of intermediate Mr (approx. 13 000), and C of low Mr (approx. 300) containing glutathione. In the presence of NADPH (1 mM), the 5′-deiodination rate by hepatic washed microsomes is greatly increased if both A and B are added and is a function of the concentrations of A, B, washed microsomes and NADPH. A is heat-labile, whereas B is heat-stable and non-dialysable. These observations provide the first evidence of an NADPH-dependent cytosolic reductase system not involving glutathione which stimulates microsomal 5′-deiodinase of normal rat liver. The present data are consistent with a deiodination mechanism involving mediation by a reductase (other than glutathione reductase) in fraction A of an NADPH-dependent reduction of a hydrogen acceptor in fraction B, followed by reduction of oxidized microsomal deiodinase by the reduced acceptor (component in fraction B).

Epidermal growth factor and interleukin-1β synergistically stimulate the production of nitric oxide in rat intestinal epithelial cells

2004 ◽  
Vol 287 (6) ◽  
pp. G1188-G1193 ◽  
Author(s):  
Katsuhiko Kitagawa ◽  
Yoshinori Hamada ◽  
Yasunori Kato ◽  
Koji Nakai ◽  
Mikio Nishizawa ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Epithelial Cells ◽  
Intestinal Epithelial Cells ◽  
Pi3 Kinase ◽  
Intestinal Epithelial ◽  
Simultaneous Addition ◽  
Epidermal Growth ◽  
Inos Induction

Epidermal growth factor (EGF) is one of the trophic factors for intestinal adaptation after small bowel transplantation (SBT). A recent report indicates that nitric oxide (NO) has cytoprotective effects on bacterial translocation (BT) after SBT. We hypothesized that EGF stimulates the expression of the inducible NO synthase (iNOS) gene in the graft after SBT, followed by increased production of NO, resulting in the decrease of BT. Intestinal epithelial cells (IEC)-6 were treated with EGF and/or IL-1β in the presence and absence of phosphatidylinositol 3-kinase (PI3-kinase) and EGF receptor kinase inhibitors (LY-294002 and tyrphostin A25). The induction of NO production and iNOS and its signal molecules, including the inhibitory protein of NF-κB (IκB), NF-κB, and Akt, were analyzed. IL-1β stimulated the degradation of IκB and the activation of NF-κB but had no effect on iNOS induction. EGF, which had no effect on the NF-κB activation and iNOS induction, stimulated the upregulation of type 1 IL-1 receptor (IL-1R1) through PI3-kinase/Akt. Simultaneous addition of EGF and IL-1β stimulated synergistically the induction of iNOS, leading to the increased production of NO. Our results indicate that EGF and IL-1β stimulate two essential signals for iNOS induction in IEC-6 cells: the upregulation of IL-1R1 through PI3-kinase/Akt and the activation of NF-κB through IκB kinase, respectively. Simultaneous addition of EGF and IL-1β can enhance the production of NO, which may contribute to the cytoprotective effect of EGF against intestinal injury.

Development of high melt strength polypropylene and its application in thermoplastic elastomeric composition

2021 ◽  
pp. 009524432110510
Author(s):  
Mousumi De Sarkar ◽  
Nishant Chandel ◽  
Shib Shankar Banerjee ◽  
Subhabrata Saha ◽  
Anil K Bhowmick ◽  
...  
Keyword(s):  
Fixed Ratio ◽  
Reactive Extrusion ◽  
Extrusion Process ◽  
Structure Property ◽  
Chain Branching ◽  
Melt Strength ◽  
Long Chain Branching ◽  
Zinc Diethyldithiocarbamate ◽  
Long Chain ◽  
High Melt Strength Polypropylene

High melt strength polypropylene (HMS-PP) with a long-chain branched structure is a modified form of polypropylene (PP) which has basic properties of regular PP but with superior melt drawability. This paper reports on the development of gel-free HMS-PP from a linear isotactic PP through the introduction of long-chain branching on its backbone via a reactive extrusion process, using dicetyl-peroxydicarbonate (PODIC) alone or in combination with a coagent. The melt strength and the mechanical properties such as impact and flexural strength of PP showed improvements with the modification with PODIC. 5000 ppm by weight of PODIC was found to provide the best balance of properties. The efficacies of zinc diethyldithiocarbamate (ZDC) and tetramethyl thiuram disulphide (TMTD) as coagents in combination with PODIC to augment properties of HMS-PP further were explored. TMTD offered slightly enhanced performance benefits as compared to ZDC at an optimized concentration of 100 ppm by weight. The application potential of HMS-PP in thermoplastic elastomeric blends of HMS-PP with ethylene-propylene-diene monomer (EPDM) rubber at a fixed ratio of 35/65 by weight was also investigated. Structure-property correlations were established between the extent of long-chain branching in the modified PP and the properties of the resultant thermoplastic elastomeric composition.

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